1. Field of the Invention
The present invention generally relates to a body positioner structured to provide healthy postures by promoting active sitting and proactive positioning. The positioner enables accurate and repeatable correlation between a user""s body and a work station by enabling quick postural adjustments based on the preferred postural excursions of the user. Particularly, the body positioner is preferably integrated with at least one work station such as, for example, a computer or manufacturing station. More particularly, the invention provides integration of the positioner with a seating task station, enabling quick dynamic adjustments for optimal alignment and orientation of the positioner and the user relative to the seating task station within a plurality of healthy postures and ergonomic ranges, to promote worker health, comfort and productivity.
2. Description of Related Art
In the early 1970""s Jerome Congleton, a leading ergonomist, was the first to introduce the concept of the neutral position to the task seating industry. Further, A. C. Mandal in a book relating to unhealthy postures of school children, emphasized the need to tilt the pelvis forward in order to maintain a proper balance of the weight of the upper body on the spine. These and other ergonomic research over the last three decades have shown that certain postural orientations, particularly during sitting, affect the body weight distribution on the spine and generally result in injury or long term pain. For the most part therefore, ergonomic research over the past three decades appears to support the concept of proper body weight distribution by maintaining certain postures. However, no system exists which would enable a person, particularly engaged in work involving task seating systems and related operations, to shift into comfortable postures within a preferred set of healthy postural configurations and ergonomic positions, quickly without disrupting work.
Several medical studies have shown that prolonged static postures in any of the natural configurations, such as for example sitting and standing, cause discomfort, pain and ultimately injury. Modern work stations such as computer related work at the office require that the operator be oriented in a sedentary position. When a subject is in a limited movement sitting position muscle stress and discomfort set in. Specifically, during sitting, the vertebral column transmits the weight of the body through the pelvis to the lower limbs. When the vertebral column experiences prolonged stress due to sedentary postures, a deformity of the spine may result leading to serious medical problems such as kyphosis which is characterized by a posterior curvature of the vertebral column. Further, prolonged sedentary sitting may contribute and/or aggravate scoliosis, characterized by a lateral curvature of the vertebral column and lordosis, characterized by an anterior curvature of the vertebral column. Movements of the vertebral column are freer in the cervical and lumbar regions and these regions are the most frequent sites of aches. The main movements of the vertebral column are flexion or forward bending, extension or backward bending, lateral bending or lateral flexion, and rotation or twisting of the vertebra relative to each other. Some circumduction which consists of flexion-extension and lateral bending also occurs. It is imperative, therefore that a body positioning system provide movement, at the very least, to the cervical and lumbar regions of the vertebral column.
In addition to the vertebral column, a body support system implemented to position a person proximal to a work station must be ergonomically balanced with the work station. In this regard the upper limb, which is the organ of manual activity, should be allowed to move freely. Further, the upper limb which includes the shoulder, arm, forearm and hand must be positioned to provide stability and to gain mobility. Because any slight injury to the upper limb is further aggravated by repeated motion of the hand and arm muscles, it is important to provide comfortable positioning and support to the upper limb at all postures related to a task seating work station.
Similarly, a well-designed body support system should consider neck and head position. The neck contains vessels, nerves, and other structures connecting the head and the trunk. There are several causes of neck pain. As it relates to neck pain resulting from bad postures, muscle strain and protrusion of a cervical intervertebral disc may be the cause. Many vital structures are located in the neck and proper positioning and support of the neck must be made to avoid muscle strain. Further, posterior positioning of the head is important to avoid strain, headache and head pain.
Thoracic support is also vital to promote good breathing and elimination of stress on the thoracic vertebrae. As is well known clinically, the lungs are the essential organs of respiration. The inspired air is brought in close relationship to the blood in the pulmonary capillaries. Thus, proper positioning and thoracic support enhances the efficiency of the lungs to supply optimal oxygen levels to the blood. This is key to worker overall health and productivity.
The lower limb is the organ of locomotion and is also a load bearing element. The parts of the lower limb are comparable to those of the upper limb. The lower limb is heavier and stronger than the upper limb. Since a vast number of vital networks of arterial vessels are located in the lower limb, it is clinically important to promote the flow of blood through these arterial vessels. Thus, in sedentary postures, frequent removal of weight off the lower limb is recommended to eliminate muscle tension, fatigue and related degenerative joint disease.
In general, the present state of the art is incapable of providing users with the option to switch to different comfortable/healthy postures while keeping them within an ergonomic range of a work station in a manner that is non-disruptive to the task being performed. Particularly, the current state of the art does not provide a xe2x80x9cactive sitting and proactive positioningxe2x80x9d system which incorporates the support of the various body parts and promotes healthy postures and comfort at work stations.
Accordingly there is a need for a body positioning system capable of providing fluidic and timely transposition of a user into various preferred and healthy postural configurations, to maintain comfortable ergonomic ranges to a task seating work station at all postures and enhance health and productivity, relative to a defined space-volume envelope of the positioning system and, preferably, to a work station integrated therewith.
The present invention is based on heretofore unrealized objectives to successfully integrate human performance with comfort and health. Specifically, in the preferred embodiment, the invention implements principles of xe2x80x9cactive sitting and proactive positioningxe2x80x9d in which the subject is temporally encouraged to change to various comfort and health postures while maintaining ergonomically compatible access and reach to a work station at all times.
The invention provides a user with a selection of discrete and dynamic medically preferred health postures. Specifically, the invention utilizes, inter alia, the principle that to prevent cumulative trauma disorder (CTD) the pelvis must always be positioned in an orientation similar to an erect/tilted position during standing. The basic discrete postures of the present invention include a recline seated posture, a recline neutral posture/breath easy posture and a recline standing posture. The invention incorporates these discrete postures to generate a full range of dynamic hybrid postures continuously shiftable and adjustable to prevent injury, discomfort and fatigue while enhancing health and comfort. Further, the invention proactively positions the user to be placed within an ergonomic range of the work station, at all postural configurations, to enhance productivity.
The invention enables the user to move in and out of the discrete and dynamic postures without disrupting the task at hand. One of the significant benefits derived from this active sitting aspect of the invention is that the user is provided with a full range of joint movement in the legs and torso during the excursion through the various postures. Further, the postures enhance the respiratory system and relieve muscle stress. The user may also perform occasional stretch exercises, by shifting through these various postures, to increase vital fluid flow and circulation in the torso and lower parts of the body.
The invention includes a body positioning system having components designed to be compatible with human physiology and enhancement of healthy postures at work stations. Specifically, the major components include a seat/back support, a body support component for below the knee and a foot rest body support all being independently and correlatively operable at the option(s) of the user to navigate through various postures while maintaining ergonomic reach to the work station. More specifically, the seat/back support and the support for below the knee comprise pressure surfaces having ergonomically optimized/compatible geometric shapes to enable a smooth transition from one posture to the next in addition to the provision of proper body support and healthy positions at all postural configurations. Further, the surfaces are made of materials specifically structured to eliminate excessive resistance, during the user""s dynamic excursions through the various postures or during any static posture, without regard to the type and fabric of clothing worn by the user. Since the pressure surfaces/bearing surfaces are implemented to shiftably serve as back and seat support at various postures the interaction between the surfaces and the users clothing is critical to promote smooth transition of the user from one posture to the other.
The controls and actuators implemented in the present invention, which control the body positioning system seat/back angle adjustment, seat height adjustment and lower body part support angle adjustment, are ergonomically designed to have a high level of accessibility and availability to the user. Further, the actuators are set to meet the anthropometric fit requirements of a world population. Particularly, the controls are designed and located to enable a user to quickly and easily shift from one posture to another without disruption of the task being performed.
The present invention further provides robust features integrated to enhance productivity and worker effectiveness. The user is generically integrated with the positioning system and work station such that all the components are positioned to be readily accessible and available to the user while enabling work to progress concurrent with multiple posture position shifting. Further, the work station is designed to attenuate the transfer of vibration to the positioner by strategically installing vibration dampeners and shock absorbing connections at points of contact between the user, the work station, work tools and the positioner.
The office environment is one of the many work areas in which the present invention could be advantageously implemented. The body positioning system is dimensionally optimized to fit into most office space and is highly mobile to be compatible with movable wall offices. Further, the system of the present invention is modularized to stand alone or to be built into multiple work station areas.
In the preferred embodiment, the controls and mechanical systems are versatile to adapt to various power supply systems. Further, ease of assembly and disassembly make the system advantageously flexible to accommodate the user""s choices and be compatible with various production and work area environments.